Sandblasted large grit, acid etched 표면처리에 따른 교정용 미니 임플랜트의 제거회전력에 관한 연구

오남희,김성훈,국윤아,이근혜,강윤구,모성서 대한치과교정학회 2006 대한치과교정학회지 Vol.36 No.5

Sandblasted large grit, acid etched(SLA) 표면처리 된 교정용 미니 임플랜트와 평활면을 가진 교정용 미니 임플랜트 사이에 제거회전력과 조직학적 소견을 통해 표면처리된 교정용 임플랜트의 임상적 가능성에 대하여 알아보고자 하였다. 실험재료로는 길이가 9.5 mm, 외경이 1.8 mm인 custom made, screw shaped, titanium implants가 사용되었다. 미니 임플랜트는 두개의 군으로 분류되었는데 SLA군은 20개의 SLA 표면처리된 미니 임플랜트이었고, 평활면군은 크기와 형태가 같지만 SLA처리공정이 생략되어 제작된 20개의 미니 임플랜트로 구성되었다. 이들은 10마리 가토의 경골에 식립되었다. 각각의 가토의 우측 경골에는 SLA군의 미니 임플랜트 2개가 식립되었고, 좌측 경골에는 평활면군의 미니 임플랜트 2개가 식립되었다. 각 군에는 식립 직후 Ni-Ti coil spring에 의해 약 150 g의 지속적인 견인력이 주어졌다. 식립 6주 후에 10마리의 가토를 희생하였고, 안정된 상태에서 Ni-Ti coil spring을 제거하였으며 digital torque gauge를 이용하여 제거 회전력을 측정하였다. 식립 6주 후에 SLA군의 경우 (8.29 Ncm) 평활면군 (3.34 Ncm)에 비해 더 높은 평균 제거회전력을 나타내었고 조직학적 소견에서도 screw 하방에서의 신생골 형성이 관찰되었다. SLA 표면처리된 미니 임플랜트는 평활면 미니 임플랜트에 비해 좀 더 강한 교정력에 저항할 수 있을 것으로 예상되었다. Objective: The purposes of this study were to evaluate the differences between sand blasted, large grit and acid-etched (SLA) treated mini-implants and smooth surface orthodontic mini-implants in relation to the removal torque as well as the histologic analysis. Methods: Custom-made, screw-shaped, titanium implants with a length of 9.5 mm and an outer diameter of 1.8 mm were divided into 2 groups; the SLA group (20 SLA treated orthodontic mini-implants) and the smooth surface group (20 smooth surface mini-implants), and placed in the tibia metaphysis of 10 rabbits. Each rabbit had 4 mini-implants placed, 2 in each tibia. The right tibia were implanted with the SLA group mini-implants and the left tibia had the smooth group mini-implants placed. Each mini-implant group were immediately applied with a continuous traction force of 150 g using a Ni-Ti coil spring. The rabbits were sacrificed 6 weeks post-surgically. Subsequently, the legs were stabilized, the Ni-Ti coil springs were removed and the mini-implants were removed under reverse torque rotation with a digital torque gauge. Results: 6 weeks after placement, the SLA group presented a higher mean removal torque value (8.29 Ncm) than the smooth group (3.34 Ncm) and histologic analysis revealed a higher new bone formation aspect along the screw in the SLA group. Conclusion: Results of this study indicates that SLA treated mini-implants may endure higher orthodontic forces without loosening.

비정형 기관지 유암종에 의한 이소성 ACTH 증후군 1례

이창훈,천남일,홍세인,정진욱,윤인석,조동혁,강호철,정동진,정민영 全南大醫大 2001 전남의대학술지 Vol.37 No.2

VDT작업별 정신사회적 스트레스와 근골격계 장애에 관한 연구

백남종,강종두,주영수,배인근,권호장,박종만,조수헌,김돈규,김재용,최홍렬 大韓産業醫學會 1998 대한직업환경의학회지 Vol.10 No.4

It has been hypothesized that jobs that have both high psychological demands and low decision latitude("job strain") can lead to musculoskeletal disorder. The objective of this study was to test whether job strain was correlated with the presence of work-related musculoskeletal disorder, especially myofascial pain syndrome(MPS). Information on demographic factors, confounders such as household load and taking care of children or not, and scores for decision latitude, job demand, and social support was obtained by self-administered questionnaire, which had been developed in Korean language, by adopting NIOSH instrument and Extended Karasek Model(16 items). All subjects were also examined by rehabilitation medicine specialists for musculoskeletal disorders. Subjects(n=370) could be categorized into 4 groups, these were, housewives(n=89), shipyard CAD workers(n=89), general female workers(n=79; nurses, insurance counselors, public officials, clerks, etc), and telephone directory assistance operators(n=113). Results from univariate analyses indicated that all demographic factors, all confounders, scores for decision latitude and social support were not associated with the risk of musculoskeletal disorder. However, score for job demand was higher in musculoskeletal disorder cases than others. In subgroup analysis, this association was convinced again, in telephone directory assistance operators. Job strain model showed that the group of telephone directory assistance operators was high-stain group, and OR of musculo skeletal disorder was 2.446(95% C. I. : 1.174, 5.096), when comparing this with the low strain group. In conclusion, job strain is a risk factor for work-related musculoskeletal disorder.

외측 미칩 갑상선에서 발생하여 다발성 전이로 발현된 유두상 갑상선암 1예

천남일,이창훈,홍세인,정진욱,윤인석,조동혁,강호철,정동진,정민영 대한내분비학회 2001 Endocrinology and metabolism Vol.16 No.4-5

만성 화농성 중이염의 세균학적 고찰

조남순,이영훈,강기훈,최제환,송태현,이병돈,장혁순,강주원,김연준 순천향의학연구소;Soonchunhyang Medical Research Institute 2000 Journal of Soonchunhyang Medical Science Vol.6 No.1

Background and Objectives : Chronic suppurative otitis media is one of the frequent diseases in otolaryngologic field. It is important to choose of antibiotics in the management of infectious disease. But the organisms in infections have been changed and resistance to antibiotics has been grown as the development of antibiotics has been achieved. And so it has been necessary to recognize the changes of organisms and resistance in antibiotics. Our study was performed to identify the pathogens isolated from discharges in chronic otitis media and evaluate the antibiotic agents, to recognize the change of to resistance to·antibiotic agents and to use the appropriate anitiotics. Materials and Methods : Retrospectively, authors reviewed the backeriologic study of 114 cases of chronic suppurative otitis media who visited the Department of Otolaryngology, Soonchunhyang University in Seoul from Nov. 1996 to Oct. 1999 and analyzed 101 strains and its sensitivity test to various antibiotics. Result : In 93 cases in which pathogenic organism was isolated, single infection was 85 cases(91.4%) and mixed infection was 8 cases(8.6%). The most frequent pathogenic organism was Staphylococcus aureus(59.4%), Pseudomonas aeruginosa(13.9%), Providencia(4.8%), Alcaligenes(3.0%) and Streptococcus pneumoniae(2.9%) were the next. Methicilline-Resistance Staphylococcus aureus was 34 cases(57.6%) of Staphylococcus aureus. Staphylococcus aureus was sensitive to Vancomycin(96.7%), Trimethoprim-Sulfamethoxazole (57.6%), Cefuroxime(42.4%) and Ciprofloxacin(40.7%) but resistant to Penicillin(94.9%). Pseudomonas aeruginosa was sentitive Amikacin(100%), Ciprofloxacin(100%) and Gentamicin(67%). Conclusion : As MRSA recently was wide spread in community accquired infection as well as nosocomial infection, we must consider strict control of MRSA.

VDT작업자에서 업무로 인한 정신사회적 스트레스에 대한 인지가 근골격계장애에 미치는 영향

백남종,하미나,조수헌,강대희,백도명,주영수,윤덕로,권호장 大韓産業醫學會 1996 대한직업환경의학회지 Vol.8 No.3

업무에 의한 정신사회적 스트레스가 근골격계 질환의 유병에 미치는 영향을 파악하기 위하여 전화안내원을 대상으로 단면적 조사연구를 수행하였다. 연구 결과 나이, 교육정도, 근무연한, 가사부담 등의 인구학적 변수는 근골격계질환의 유병에 영향을 미치지 않는 것으로 분석되었다. 정신사회적 스트레스 중 업무요구도가 높다고 느끼는 집단에서 그렇지 않은 집단에 비해 근골격계 질환의 유병률이 통계적으로 유의하게 높게 나타났으나 업무재량도나 사회적지지도는 근골격계질환과 유의한 상관관계를 발견할 수 없었다. 그러나 업무요구도는 높고 업무재량도는 낮다고 느끼는 '근무긴장도가 가장 높은 군'은 업무요구도는 낮고 업무재량도는 높다고 느끼는 '근무긴장도가 낮은 군'에 비해 근골격계 질환의 발생위험이 통계적으로 유의하게 높은 것으로 나타났다. 본 연구의 결과는 업무로 인한 정신사회적 스트레스에 대한 인지 정도에 따라 근골격계질환의 유병률이 달라짐을 시사하고 있다. 따라서 작업관련성 근골격계질환의 예방을 위해서는 기존의 인간공학적 접근 이외에 스트레스를 감소시키려는 노력이 동시에 진행되어야 할 것으로 생각한다. A cross-sectional study was conducted to assess the association between perceived occupational psychosocial stress at work and the work-related musculoskeletal disorder(WRMSD) among employees using video display terminals. The study included 111 female telecommunication employees from three companies at ChungBuk province. Cases of WRMSD were defined using symptom questionnaire and physical examination conducted by rehabilitation specialist. Information on demographics, individual factors, and perceived psychosocial stress, were obtained by self-administered questionnaire. For assessing perceived psychosocial stress, we used variables from 'job strain model' proposed by Karasek. Associations between perceived psychosocial stress and WRMSD were assessed by multiple logistic regression models. Forty nine(44% to the total) subjects met our operational definition for WRMSD. Age, seniority, housing load were not associated with WRMSD. Perceived psychosocial stress was associated with WRMSD[odds ratio=3.28, 95% confidence interval: 1.05-10.19]. This study suggests that perceived occupational psychosocial stress is related to the prevalence of WRMSD.

Mastoparan B의 항균 활성 및 용혈 작용에 미치는 소수성도와 양친매성의 영향

이봉헌,김광호,장태식,박남규,박장수,강신원 부산대학교 유전공학연구소 1998 분자생물학 연구보 Vol.14 No.-

Tetradecapeptide인 Mastoparan B(MP B)와 이의〔Ala〕-MP B유도체들을 합성하고 항균 활성 및 용혈 작용을 측정하여 MP B의 활성에 미치는 소수성도(hydrophobicity)와 양친매성(amphiphilicity)의 영향을 비교하였다. 그 결과 MP B와 소수성도가 MP B 보다 큰〔Ala^2〕-,〔Ala^4〕-MP B유도체가 큰 항균 활성을 나타내었으며, 소수성도가 MP B보다 작은〔Ala^6〕-MP B유도체의 활성은 MP B와 비슷하거나 작게 나타나 소수성도가 큰 유도체일수록 항균활성을 크게 나타내었다. 그러나 MP B보다 소수성도가 큰 유도체인〔Ala^9〕-MP B는 Ala에 의한 Trp의 치환때문에 MP B보다 작은 활성을 나타내었다.용혈 활성 측정 결과 MP B보다 소수성도가 큰〔Ala^2〕-,〔Ala^4〕-MP B유도체가 각각100.0%와 69.4%로써 용혈 작용을 크게 나타냈으나, 소수성도가 작은〔Ala^6〕-MP B유도체는 6.1%로써 가장 작은 용혈 작용을 나타내었고 Trp대신 Ala으로 치환한 소수성도가 큰 유도체인〔Ala^9〕-MP B는 MP B보다 작은 26.0%의 용혈 작용을 나타내었다. 그러므로 용혈 작용은 소수성도가 클수록 증가하였으며 양친매성이 활성에 미치는 영향은 적었다. Tetradecapeptide.Mastoparan B(MP B)and its〔Ala^2 〕-,〔Ala^4〕-,〔Ala^6〕-,〔Ala^9〕-MP Bderivatives were synthesized, and then their antibacterical and hemolitic were to examine the effect of hydrophobicity and ampiphilicity on the MP B-induced those activities. MP B and more hydrophobic〔Ala^2 〕-,〔Ala^4〕-MP B showed stronger antibacterical activity and less hydrophobic〔Ala^6〕-MP B than MP B did similar or weaker activity, so more hydrophobic〔Ala〕-MP B derivative had stronger activity. But more hydrophobic〔Ala^9〕-MP B than MP B showed weaker activity because of its Trp subsitution by Ala. On the other hand,〔Ala^2 〕-and〔Ala^4〕-MP B showed 100.0% and 69.4% hemoiytic activity, but〔Ala^6〕-MP B did the weakwst activity(6.1%)and〔Ala^9〕-MP B, weaker activity(26.0%) than MP B.Therefore, more hydrophobic〔Ala〕-MP B derviative had stronger activity and the effect of ampiphilicity on the activity was weak.

CuO를 열확산시킨(Sr.Ca)TiO_(3) 입계층 커패시터의 전기적 특성

최운식,강재훈,오남석 대불대학교 2002 大佛大學校大學院 硏究論文集 Vol.- No.1

In this paper, the Sr_(1-x)Ca_(x)TiO_(3)(0≤x≤0.2)-based grain boundary layer ceramics were fabricated to measured dielectric properties with the sintering temperature and the thermal treatment time. The sintering temperature and time were 1420∼1520℃, 4hours, and the thermal treatment temperature and time of the specimen were 1150℃, 1, 2, 3,hours, respectively. The structural and the dielectric properties were investigated by SEM, X-ray, HP4194A and K6517. The average grain size was increased with increasing the sintering temperature, but decreased to 15㏖% with increasing content of Ca. X-ray diffraction analysis results showed that all specimens were the cubic structure, the main peaks were of Ca. The appropriate thermal treatment temperature and time of CuO to obtain dielectric properties of ε_(γ)>50000, tan δ<0.05 and ΔC<±10% were 1150℃ and 2hours, respectively.

초음파 에너지를 부가한 물-경유 에멀젼유의 디젤기관 성능에 관한 연구

권기린,강남훈 제주대학교 공과대학 첨단기술연구소 2001 尖端技術硏究所論文集 Vol.12 No.2

This study was undertaken to investigate the engine output, fuel consumption and its brake thermal efficiency of diesel fuel(DF), ultrasonic energy adding diesel fuel(UDF) and ultrasonic energy adding emulsified fuel(UEF) according to the variation of the speed of engine revolution through engine performance test device under the circumstances of electrical load (4/4) and 80℃. The results obtained are as follows: 1. In the case of UDF, as a result of fuel atomization combustion efficiency became good and accordingly fuel consumption rate decreased by 2∼2.5%, brake horsepower increased by 1.32% maximum. According to decrease in fuel consumption rate and increase in brake horsepower, specific fuel consumption rate was improved by 1.8∼3.5%, and brake thermal efficiency was improved by 2∼2.6%. 2. When using UEF, torque and brake horsepower decreased by 0.4∼1.35%, 0.41∼1.34%, fuel consumption rate increased by 3.15∼4.05%. 3. When using UEF, in spite of the increase in brake horsepower and fuel consumption rate, owing to the small calorific value of emulsified fuel, brake thermal efficiency was improved by 6.1∼7.3%. 4. In the case of UDF, torque was improved, whereas when using UEF, torque was decreased.

콜레스테롤 생합성 저해제 검색법의 개발

임종철,이남훈,김한균,염형렬,이대호,강현석,류형선,명재일,김완,신부안 全南大醫大 2001 전남의대학술지 Vol.37 No.2